A Little Confused

[jhammel85]

Well like the title says..I'm a little bit confused on a code that I found in my truck.
I found a code 87 that popped up twice, back to back after the long pause when checking for codes. Others were all code 11's...

Code 87:
- Fuel pump primary circuit failure. When the FP relay was activated by the EEC, voltage was not detected on the control circuit.

- Voltage was not detected on Fuel Pump Monitor while the engine was running.

After I checked this out, I swapped computers with one thats been out for a while now and I got the same code. I thought this was pretty odd unless something is wired incorrectly. I've found some hack job wiring in this truck so I would be surprised if something was bypassed at some point. Another thing worth throwing out there is that the truck starts and runs so the fuel pumps and their relays seem to be fine.

I do have some small issues at the moment. If the truck is started warm, it will spit and sputter and run rich for a few seconds when you first give it throttle to go up the street..During this it will hunt for idle and you can smell the fuel from the pipe. Other than that, it also has a slight misfire around 2k and at some other points in the RPM range..I'm chalking that up to my timing needing to be adjusted..

So..Any ideas?

 

[Psychopete]

The 87 code sounds like you may need to address corrosion in the fuel pump relay harness (or even ECC), or that relay maybe on the fritz. That is going to be a hard one to diagnose.

As far as the second issue, when was the last the time the ECT was replaced?

 

[jhammel85]

Thanks for responding.

The Fuel Pump relay is actually brand new because I had it get wet in the rain recently. What about the EEC relay??

As far as corrosion, I'll have to give that a shot. Now I did notice that when both of these EEC's are used for a long time, there can be a tiny bit of corrosion on the pins of the computer. Don't know why I didnt think of this but I may have to try to clean out the ports on the harness. This weekend I am getting an '88 EEC (Finally!!) so I will have to try to clean it then.

Any suggestions for cleaning the harness's plug?

As far as the ECT goes, It was replaced in Feb of 2010. The truck has done this since I got it in December of 09. The replacement of that ECT was a shot in the dark, at the time, to fix this issue.

 

[jhammel85]

Alright...

So I installed the '88 EEC which fixed the drivability RPM issue I had going on along with just overall health of the engine. I think you can set a cup of coffee on the upper manifold and never see a ripple as it idles now.

However, The warm start problem is still there. So far, it's still intermittent like it always has been but what it does now is hunt for idle and thats it. Once you give it gas and go, it goes away (unless the EEC pics up the hunting 1st and puts an end to it.)
I plan to check the new EEC in a few days for codes. I'm also going to check out the wiring to see if somethings been hacked.

Any ideas anyone?